<?php

/*
 * Copyright 2008 the original author or authors.
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#namespace tehframework\iocc\valueholders;

#use \Exception;
#use tehframework\iocc\ObjectBuildingException;
#use tehframework\iocc\Container;
#use tehframework\iocc\ContainerAware;
#use tehframework\iocc\ValueHolder;

class CallbackValueHolder implements ValueHolder
{
	/**
	 * @var CallableValueHolder
	 */
	private $callable;
	
	/**
	 * @var array
	 */
	private $arguments;
	
	/**
	 * @param  CallableValueHolder $callable
	 * @param  array? $arguments
	 */
	public function __construct(CallableValueHolder $callable, array $arguments = array())
	{
		$this->callable  = $callable;
		$this->arguments = $arguments;
	}
	
	/**
	 * @param  Container $container
	 * @return mixed
	 * @throws ObjectBuildingException
	 */
	public function getValue(Container $container)
	{
		$callable = $this->callable->getValue($container);
		
		if (count($this->arguments) === 0)
		{
			return call_user_func($callable);
		}
		
		$arguments = array();
		
		foreach ($this->arguments as &$argument)
		{
			if ($argument instanceof ContainerAware)
			{
				$argument->setContainer($container);
			}
			
			if ($argument instanceof ValueHolder)
			{
				$argument = $argument->getValue($container);
			}
			
			$arguments[] = $argument;
		}
		
		try
		{
			return call_user_func_array($callable, $arguments);
		}
		catch (ObjectBuildingException $x)
		{
			throw $x;
		}
		catch (Exception $x)
		{
			throw new ObjectBuildingException('Exception while resolving a callback value.', null, $x);
		}
	}
}